| Message ID | 1374786537-10726-2-git-send-email-ben.dooks@codethink.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 2013-07-25 at 22:08 +0100, Ben Dooks wrote: > If we are running BE8, the data and instruction endian-ness do not > match, so use <asm/opcodes.h> to correctly translate memory accesses > into ARM instructions. > > Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>y > --- > arch/arm/kernel/kprobes-common.c | 14 ++++++++------ > arch/arm/kernel/kprobes.c | 9 +++++---- > 2 files changed, 13 insertions(+), 10 deletions(-) > > diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c > index 18a7628..c0b202e 100644 > --- a/arch/arm/kernel/kprobes-common.c > +++ b/arch/arm/kernel/kprobes-common.c > @@ -14,6 +14,7 @@ > #include <linux/kernel.h> > #include <linux/kprobes.h> > #include <asm/system_info.h> > +#include <asm/opcodes.h> > > #include "kprobes.h" > > @@ -305,7 +306,8 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) > > if (handler) { > /* We can emulate the instruction in (possibly) modified form */ > - asi->insn[0] = (insn & 0xfff00000) | (rn << 16) | reglist; > + asi->insn[0] = __opcode_to_mem_arm((insn & 0xfff00000) | > + (rn << 16) | reglist); > asi->insn_handler = handler; > return INSN_GOOD; > } > @@ -338,9 +340,9 @@ prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, > thumb_insn[2] = 0x4770; /* Thumb bx lr */ The line above and the one before it not in this diff also need fixing by changing to __opcode_to_mem_thumb16(0x4770). > return insn; > } > - asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ > + asi->insn[1] = __opcode_to_mem_arm(0xe12fff1e); /* ARM bx lr */ > #else > - asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ > + asi->insn[1] = __opcode_to_mem_arm(0xe1a0f00e); /* mov pc, lr */ > #endif > /* Make an ARM instruction unconditional */ > if (insn < 0xe0000000) > @@ -360,12 +362,12 @@ set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, > if (thumb) { > u16 *ip = (u16 *)asi->insn; > if (is_wide_instruction(insn)) > - *ip++ = insn >> 16; > - *ip++ = insn; > + *ip++ = ___asm_opcode_to_mem_thumb16(insn >> 16); > + *ip++ = ___asm_opcode_to_mem_thumb16(insn); Should these two ___asm_opcode_thumb32_compose() not be __opcode_thumb32_compose() ? > return; > } > #endif > - asi->insn[0] = insn; > + asi->insn[0] = __opcode_to_mem_arm(insn); > } > > /* > diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c > index 170e9f3..3775af1 100644 > --- a/arch/arm/kernel/kprobes.c > +++ b/arch/arm/kernel/kprobes.c > @@ -26,6 +26,7 @@ > #include <linux/stop_machine.h> > #include <linux/stringify.h> > #include <asm/traps.h> > +#include <asm/opcodes.h> > #include <asm/cacheflush.h> > > #include "kprobes.h" > @@ -62,10 +63,10 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) > #ifdef CONFIG_THUMB2_KERNEL > thumb = true; > addr &= ~1; /* Bit 0 would normally be set to indicate Thumb code */ > - insn = ((u16 *)addr)[0]; > + insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]); > if (is_wide_instruction(insn)) { > - insn <<= 16; > - insn |= ((u16 *)addr)[1]; > + u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]); > + insn = ___asm_opcode_thumb32_compose(insn, inst2); Again, __opcode_thumb32_compose instead of ___asm_opcode_thumb32_compose > decode_insn = thumb32_kprobe_decode_insn; > } else > decode_insn = thumb16_kprobe_decode_insn; > @@ -73,7 +74,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) > thumb = false; > if (addr & 0x3) > return -EINVAL; > - insn = *p->addr; > + insn = __mem_to_opcode_arm(*p->addr); > decode_insn = arm_kprobe_decode_insn; > #endif >
On 29/07/13 09:01, Jon Medhurst (Tixy) wrote: > On Thu, 2013-07-25 at 22:08 +0100, Ben Dooks wrote: >> If we are running BE8, the data and instruction endian-ness do not >> match, so use<asm/opcodes.h> to correctly translate memory accesses >> into ARM instructions. >> >> Signed-off-by: Ben Dooks<ben.dooks@codethink.co.uk>y >> --- >> arch/arm/kernel/kprobes-common.c | 14 ++++++++------ >> arch/arm/kernel/kprobes.c | 9 +++++---- >> 2 files changed, 13 insertions(+), 10 deletions(-) >> >> diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c >> index 18a7628..c0b202e 100644 >> --- a/arch/arm/kernel/kprobes-common.c >> +++ b/arch/arm/kernel/kprobes-common.c >> @@ -14,6 +14,7 @@ >> #include<linux/kernel.h> >> #include<linux/kprobes.h> >> #include<asm/system_info.h> >> +#include<asm/opcodes.h> >> >> #include "kprobes.h" >> >> @@ -305,7 +306,8 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) >> >> if (handler) { >> /* We can emulate the instruction in (possibly) modified form */ >> - asi->insn[0] = (insn& 0xfff00000) | (rn<< 16) | reglist; >> + asi->insn[0] = __opcode_to_mem_arm((insn& 0xfff00000) | >> + (rn<< 16) | reglist); >> asi->insn_handler = handler; >> return INSN_GOOD; >> } >> @@ -338,9 +340,9 @@ prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, >> thumb_insn[2] = 0x4770; /* Thumb bx lr */ > > The line above and the one before it not in this diff also need fixing > by changing to __opcode_to_mem_thumb16(0x4770). IIRC, these are then fixed by the set_emulated instruction, which is also why the insn return is not swapped. >> return insn; >> } >> - asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ >> + asi->insn[1] = __opcode_to_mem_arm(0xe12fff1e); /* ARM bx lr */ >> #else >> - asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ >> + asi->insn[1] = __opcode_to_mem_arm(0xe1a0f00e); /* mov pc, lr */ >> #endif >> /* Make an ARM instruction unconditional */ >> if (insn< 0xe0000000) >> @@ -360,12 +362,12 @@ set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, >> if (thumb) { >> u16 *ip = (u16 *)asi->insn; >> if (is_wide_instruction(insn)) >> - *ip++ = insn>> 16; >> - *ip++ = insn; >> + *ip++ = ___asm_opcode_to_mem_thumb16(insn>> 16); >> + *ip++ = ___asm_opcode_to_mem_thumb16(insn); > > > Should these two ___asm_opcode_thumb32_compose() not be > __opcode_thumb32_compose() ? I decided to leave this as is. >> return; >> } >> #endif >> - asi->insn[0] = insn; >> + asi->insn[0] = __opcode_to_mem_arm(insn); >> } >> >> /* >> diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c >> index 170e9f3..3775af1 100644 >> --- a/arch/arm/kernel/kprobes.c >> +++ b/arch/arm/kernel/kprobes.c >> @@ -26,6 +26,7 @@ >> #include<linux/stop_machine.h> >> #include<linux/stringify.h> >> #include<asm/traps.h> >> +#include<asm/opcodes.h> >> #include<asm/cacheflush.h> >> >> #include "kprobes.h" >> @@ -62,10 +63,10 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) >> #ifdef CONFIG_THUMB2_KERNEL >> thumb = true; >> addr&= ~1; /* Bit 0 would normally be set to indicate Thumb code */ >> - insn = ((u16 *)addr)[0]; >> + insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]); >> if (is_wide_instruction(insn)) { >> - insn<<= 16; >> - insn |= ((u16 *)addr)[1]; >> + u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]); >> + insn = ___asm_opcode_thumb32_compose(insn, inst2); > > Again, __opcode_thumb32_compose instead of > ___asm_opcode_thumb32_compose > >> decode_insn = thumb32_kprobe_decode_insn; >> } else >> decode_insn = thumb16_kprobe_decode_insn; >> @@ -73,7 +74,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) >> thumb = false; >> if (addr& 0x3) >> return -EINVAL; >> - insn = *p->addr; >> + insn = __mem_to_opcode_arm(*p->addr); >> decode_insn = arm_kprobe_decode_insn; >> #endif >> >
On Wed, Jul 31, 2013 at 08:43:07PM +0100, Ben Dooks wrote: > On 29/07/13 09:01, Jon Medhurst (Tixy) wrote: > >On Thu, 2013-07-25 at 22:08 +0100, Ben Dooks wrote: > >>If we are running BE8, the data and instruction endian-ness do not > >>match, so use<asm/opcodes.h> to correctly translate memory accesses > >>into ARM instructions. > >> > >>Signed-off-by: Ben Dooks<ben.dooks@codethink.co.uk>y > >>--- > >> arch/arm/kernel/kprobes-common.c | 14 ++++++++------ > >> arch/arm/kernel/kprobes.c | 9 +++++---- > >> 2 files changed, 13 insertions(+), 10 deletions(-) > >> > >>diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c > >>index 18a7628..c0b202e 100644 > >>--- a/arch/arm/kernel/kprobes-common.c > >>+++ b/arch/arm/kernel/kprobes-common.c > >>@@ -14,6 +14,7 @@ > >> #include<linux/kernel.h> > >> #include<linux/kprobes.h> > >> #include<asm/system_info.h> > >>+#include<asm/opcodes.h> > >> > >> #include "kprobes.h" > >> > >>@@ -305,7 +306,8 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) > >> > >> if (handler) { > >> /* We can emulate the instruction in (possibly) modified form */ > >>- asi->insn[0] = (insn& 0xfff00000) | (rn<< 16) | reglist; > >>+ asi->insn[0] = __opcode_to_mem_arm((insn& 0xfff00000) | > >>+ (rn<< 16) | reglist); > >> asi->insn_handler = handler; > >> return INSN_GOOD; > >> } > >>@@ -338,9 +340,9 @@ prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, > >> thumb_insn[2] = 0x4770; /* Thumb bx lr */ > > > >The line above and the one before it not in this diff also need fixing > >by changing to __opcode_to_mem_thumb16(0x4770). > > IIRC, these are then fixed by the set_emulated instruction, which is > also why the insn return is not swapped. > > >> return insn; > >> } > >>- asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ > >>+ asi->insn[1] = __opcode_to_mem_arm(0xe12fff1e); /* ARM bx lr */ > >> #else > >>- asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ > >>+ asi->insn[1] = __opcode_to_mem_arm(0xe1a0f00e); /* mov pc, lr */ > >> #endif > >> /* Make an ARM instruction unconditional */ > >> if (insn< 0xe0000000) > >>@@ -360,12 +362,12 @@ set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, > >> if (thumb) { > >> u16 *ip = (u16 *)asi->insn; > >> if (is_wide_instruction(insn)) > >>- *ip++ = insn>> 16; > >>- *ip++ = insn; > >>+ *ip++ = ___asm_opcode_to_mem_thumb16(insn>> 16); > >>+ *ip++ = ___asm_opcode_to_mem_thumb16(insn); > > > > > >Should these two ___asm_opcode_thumb32_compose() not be > >__opcode_thumb32_compose() ? > > I decided to leave this as is. Although the intent is not made as clear in the header as it could be, the ___asm() functions are not supposed to be used directly: __opcode_thumb32_compose() will map to the correct thing based on whether we are preprocessing assembler or C. In particular, ___asm_opcode_thumb32_compose() will give you inefficient swabbing if used directly in C. > >> return; > >> } > >> #endif > >>- asi->insn[0] = insn; > >>+ asi->insn[0] = __opcode_to_mem_arm(insn); > >> } > >> > >> /* > >>diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c > >>index 170e9f3..3775af1 100644 > >>--- a/arch/arm/kernel/kprobes.c > >>+++ b/arch/arm/kernel/kprobes.c > >>@@ -26,6 +26,7 @@ > >> #include<linux/stop_machine.h> > >> #include<linux/stringify.h> > >> #include<asm/traps.h> > >>+#include<asm/opcodes.h> > >> #include<asm/cacheflush.h> > >> > >> #include "kprobes.h" > >>@@ -62,10 +63,10 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) > >> #ifdef CONFIG_THUMB2_KERNEL > >> thumb = true; > >> addr&= ~1; /* Bit 0 would normally be set to indicate Thumb code */ > >>- insn = ((u16 *)addr)[0]; > >>+ insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]); > >> if (is_wide_instruction(insn)) { > >>- insn<<= 16; > >>- insn |= ((u16 *)addr)[1]; > >>+ u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]); > >>+ insn = ___asm_opcode_thumb32_compose(insn, inst2); > > > >Again, __opcode_thumb32_compose instead of > >___asm_opcode_thumb32_compose ditto, this should be changed. Cheers ---Dave
On 02/08/13 14:57, Dave Martin wrote: > On Wed, Jul 31, 2013 at 08:43:07PM +0100, Ben Dooks wrote: >> On 29/07/13 09:01, Jon Medhurst (Tixy) wrote: >>> On Thu, 2013-07-25 at 22:08 +0100, Ben Dooks wrote: >>>> If we are running BE8, the data and instruction endian-ness do not >>>> match, so use<asm/opcodes.h> to correctly translate memory accesses >>>> into ARM instructions. >>>> >>>> Signed-off-by: Ben Dooks<ben.dooks@codethink.co.uk>y >>>> --- >>>> arch/arm/kernel/kprobes-common.c | 14 ++++++++------ >>>> arch/arm/kernel/kprobes.c | 9 +++++---- >>>> 2 files changed, 13 insertions(+), 10 deletions(-) >>>> >>>> diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c >>>> index 18a7628..c0b202e 100644 >>>> --- a/arch/arm/kernel/kprobes-common.c >>>> +++ b/arch/arm/kernel/kprobes-common.c >>>> @@ -14,6 +14,7 @@ >>>> #include<linux/kernel.h> >>>> #include<linux/kprobes.h> >>>> #include<asm/system_info.h> >>>> +#include<asm/opcodes.h> >>>> >>>> #include "kprobes.h" >>>> >>>> @@ -305,7 +306,8 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) >>>> >>>> if (handler) { >>>> /* We can emulate the instruction in (possibly) modified form */ >>>> - asi->insn[0] = (insn& 0xfff00000) | (rn<< 16) | reglist; >>>> + asi->insn[0] = __opcode_to_mem_arm((insn& 0xfff00000) | >>>> + (rn<< 16) | reglist); >>>> asi->insn_handler = handler; >>>> return INSN_GOOD; >>>> } >>>> @@ -338,9 +340,9 @@ prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, >>>> thumb_insn[2] = 0x4770; /* Thumb bx lr */ >>> >>> The line above and the one before it not in this diff also need fixing >>> by changing to __opcode_to_mem_thumb16(0x4770). >> >> IIRC, these are then fixed by the set_emulated instruction, which is >> also why the insn return is not swapped. >> >>>> return insn; >>>> } >>>> - asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ >>>> + asi->insn[1] = __opcode_to_mem_arm(0xe12fff1e); /* ARM bx lr */ >>>> #else >>>> - asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ >>>> + asi->insn[1] = __opcode_to_mem_arm(0xe1a0f00e); /* mov pc, lr */ >>>> #endif >>>> /* Make an ARM instruction unconditional */ >>>> if (insn< 0xe0000000) >>>> @@ -360,12 +362,12 @@ set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, >>>> if (thumb) { >>>> u16 *ip = (u16 *)asi->insn; >>>> if (is_wide_instruction(insn)) >>>> - *ip++ = insn>> 16; >>>> - *ip++ = insn; >>>> + *ip++ = ___asm_opcode_to_mem_thumb16(insn>> 16); >>>> + *ip++ = ___asm_opcode_to_mem_thumb16(insn); >>> >>> >>> Should these two ___asm_opcode_thumb32_compose() not be >>> __opcode_thumb32_compose() ? >> >> I decided to leave this as is. > > Although the intent is not made as clear in the header as it could be, > the ___asm() functions are not supposed to be used directly: > __opcode_thumb32_compose() will map to the correct thing based on > whether we are preprocessing assembler or C. > > In particular, ___asm_opcode_thumb32_compose() will give you inefficient > swabbing if used directly in C. > >>>> return; >>>> } >>>> #endif >>>> - asi->insn[0] = insn; >>>> + asi->insn[0] = __opcode_to_mem_arm(insn); >>>> } >>>> >>>> /* >>>> diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c >>>> index 170e9f3..3775af1 100644 >>>> --- a/arch/arm/kernel/kprobes.c >>>> +++ b/arch/arm/kernel/kprobes.c >>>> @@ -26,6 +26,7 @@ >>>> #include<linux/stop_machine.h> >>>> #include<linux/stringify.h> >>>> #include<asm/traps.h> >>>> +#include<asm/opcodes.h> >>>> #include<asm/cacheflush.h> >>>> >>>> #include "kprobes.h" >>>> @@ -62,10 +63,10 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) >>>> #ifdef CONFIG_THUMB2_KERNEL >>>> thumb = true; >>>> addr&= ~1; /* Bit 0 would normally be set to indicate Thumb code */ >>>> - insn = ((u16 *)addr)[0]; >>>> + insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]); >>>> if (is_wide_instruction(insn)) { >>>> - insn<<= 16; >>>> - insn |= ((u16 *)addr)[1]; >>>> + u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]); >>>> + insn = ___asm_opcode_thumb32_compose(insn, inst2); >>> >>> Again, __opcode_thumb32_compose instead of >>> ___asm_opcode_thumb32_compose > > ditto, this should be changed. > > Cheers > ---Dave Yes, already fixed thanks.
On Wed, Jul 31, 2013 at 08:43:07PM +0100, Ben Dooks wrote: > On 29/07/13 09:01, Jon Medhurst (Tixy) wrote: > >On Thu, 2013-07-25 at 22:08 +0100, Ben Dooks wrote: > >>If we are running BE8, the data and instruction endian-ness do not > >>match, so use<asm/opcodes.h> to correctly translate memory accesses > >>into ARM instructions. > >> > >>Signed-off-by: Ben Dooks<ben.dooks@codethink.co.uk>y > >>--- > >> arch/arm/kernel/kprobes-common.c | 14 ++++++++------ > >> arch/arm/kernel/kprobes.c | 9 +++++---- > >> 2 files changed, 13 insertions(+), 10 deletions(-) > >> > >>diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c > >>index 18a7628..c0b202e 100644 > >>--- a/arch/arm/kernel/kprobes-common.c > >>+++ b/arch/arm/kernel/kprobes-common.c > >>@@ -14,6 +14,7 @@ > >> #include<linux/kernel.h> > >> #include<linux/kprobes.h> > >> #include<asm/system_info.h> > >>+#include<asm/opcodes.h> > >> > >> #include "kprobes.h" > >> > >>@@ -305,7 +306,8 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) > >> > >> if (handler) { > >> /* We can emulate the instruction in (possibly) modified form */ > >>- asi->insn[0] = (insn& 0xfff00000) | (rn<< 16) | reglist; > >>+ asi->insn[0] = __opcode_to_mem_arm((insn& 0xfff00000) | > >>+ (rn<< 16) | reglist); > >> asi->insn_handler = handler; > >> return INSN_GOOD; > >> } > >>@@ -338,9 +340,9 @@ prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, > >> thumb_insn[2] = 0x4770; /* Thumb bx lr */ > > > >The line above and the one before it not in this diff also need fixing > >by changing to __opcode_to_mem_thumb16(0x4770). > > IIRC, these are then fixed by the set_emulated instruction, which is > also why the insn return is not swapped. Ah, I see. I think it would be better to have consistent behaviour between the ARM and Thumb cases here: in its current form, this patch makes set_emulated_insn() responsible for the swabbing in the Thumb case and not in the ARM case. Doing it in the same place for both cases would be preferable ... or was there a reason why this doesn't work? Cheers ---Dave > >> return insn; > >> } > >>- asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ > >>+ asi->insn[1] = __opcode_to_mem_arm(0xe12fff1e); /* ARM bx lr */ > >> #else > >>- asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ > >>+ asi->insn[1] = __opcode_to_mem_arm(0xe1a0f00e); /* mov pc, lr */ > >> #endif > >> /* Make an ARM instruction unconditional */ > >> if (insn< 0xe0000000) > >>@@ -360,12 +362,12 @@ set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, > >> if (thumb) { > >> u16 *ip = (u16 *)asi->insn; > >> if (is_wide_instruction(insn)) > >>- *ip++ = insn>> 16; > >>- *ip++ = insn; > >>+ *ip++ = ___asm_opcode_to_mem_thumb16(insn>> 16); > >>+ *ip++ = ___asm_opcode_to_mem_thumb16(insn); > > [...]
diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c index 18a7628..c0b202e 100644 --- a/arch/arm/kernel/kprobes-common.c +++ b/arch/arm/kernel/kprobes-common.c @@ -14,6 +14,7 @@ #include <linux/kernel.h> #include <linux/kprobes.h> #include <asm/system_info.h> +#include <asm/opcodes.h> #include "kprobes.h" @@ -305,7 +306,8 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) if (handler) { /* We can emulate the instruction in (possibly) modified form */ - asi->insn[0] = (insn & 0xfff00000) | (rn << 16) | reglist; + asi->insn[0] = __opcode_to_mem_arm((insn & 0xfff00000) | + (rn << 16) | reglist); asi->insn_handler = handler; return INSN_GOOD; } @@ -338,9 +340,9 @@ prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, thumb_insn[2] = 0x4770; /* Thumb bx lr */ return insn; } - asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ + asi->insn[1] = __opcode_to_mem_arm(0xe12fff1e); /* ARM bx lr */ #else - asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ + asi->insn[1] = __opcode_to_mem_arm(0xe1a0f00e); /* mov pc, lr */ #endif /* Make an ARM instruction unconditional */ if (insn < 0xe0000000) @@ -360,12 +362,12 @@ set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, if (thumb) { u16 *ip = (u16 *)asi->insn; if (is_wide_instruction(insn)) - *ip++ = insn >> 16; - *ip++ = insn; + *ip++ = ___asm_opcode_to_mem_thumb16(insn >> 16); + *ip++ = ___asm_opcode_to_mem_thumb16(insn); return; } #endif - asi->insn[0] = insn; + asi->insn[0] = __opcode_to_mem_arm(insn); } /* diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index 170e9f3..3775af1 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -26,6 +26,7 @@ #include <linux/stop_machine.h> #include <linux/stringify.h> #include <asm/traps.h> +#include <asm/opcodes.h> #include <asm/cacheflush.h> #include "kprobes.h" @@ -62,10 +63,10 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) #ifdef CONFIG_THUMB2_KERNEL thumb = true; addr &= ~1; /* Bit 0 would normally be set to indicate Thumb code */ - insn = ((u16 *)addr)[0]; + insn = __mem_to_opcode_thumb16(((u16 *)addr)[0]); if (is_wide_instruction(insn)) { - insn <<= 16; - insn |= ((u16 *)addr)[1]; + u16 inst2 = __mem_to_opcode_thumb16(((u16 *)addr)[1]); + insn = ___asm_opcode_thumb32_compose(insn, inst2); decode_insn = thumb32_kprobe_decode_insn; } else decode_insn = thumb16_kprobe_decode_insn; @@ -73,7 +74,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) thumb = false; if (addr & 0x3) return -EINVAL; - insn = *p->addr; + insn = __mem_to_opcode_arm(*p->addr); decode_insn = arm_kprobe_decode_insn; #endif
If we are running BE8, the data and instruction endian-ness do not match, so use <asm/opcodes.h> to correctly translate memory accesses into ARM instructions. Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>y --- arch/arm/kernel/kprobes-common.c | 14 ++++++++------ arch/arm/kernel/kprobes.c | 9 +++++---- 2 files changed, 13 insertions(+), 10 deletions(-)